On the tram back to the Piazza del Popolo after the game the Tartan Army celebrated with a potent vocal mix of Peroni and the Proclaimers.

In between swigs of the local brew they lustily declared they would walk 5000 miles to savour success for their team.

That’s 10 times further than Craig and Charlie Reid ever would wander but this hard-pressed bunch of fans have felt every painful inch of every mile of their extended journey.

However, half an hour earlier at the Olympic Stadium Johnson had been at pains to suggest a destination had not been reached, although an important milestone may just have been passed.

The first half of this game was as poor as anything the Scots have served up in the first two fixtures of the Six Nations but the second half might turn out to be the making of some of the less experienced players in the squad.

Johnson said: “They showed good resolve, great character and I’m proud of them but I’m not going to get carried away – and I wouldn’t get carried away with a loss either.

“There were good things in our game and I was glad for the boys that good fortune came their way. But we’ll work on the things we still need to improve.”

The positives for Scotland on a sunny afternoon in Rome included the grace under pressure of playmaker Weir, who delivered with unerring accuracy from 45 metres with just 10 seconds left to give his side their first win of the championship and first in Italy since 2006.

Centre Alex Dunbar became the first Scot since Sean Lamont, also in 2006, to score two tries in one game. The visiting fans screamed at him to offload as he barged towards the line for his second score but he backed himself to go all the way and delivered. Scottish players have not always been so brave.

Three weeks ago the Scots lost a try on the stroke of half-time against Ireland and buckled in Dublin. This time they refused to be cowed, although admittedly the Irish are a class above the side destined for the wooden spoon for the 10th time in 15 years.

The Scottish lineout was again dominant and it was satisfying to watch that blonde mop of Richie Gray’s bobbing up time and again on his return as he and fellow lock Jim Hamilton gave the backs a platform to play.

Johnson added: “When they scored just before half-time, similar to Ireland, and with a 10-2 penalty count against us I wasn’t sure how to face them in the changing room. But we talked about what we needed to do and they showed a bit of composure.

“It was good for Dunky to get the final kick. He hasn’t been in that position before and I’m glad he has learned he can do that because I can’t teach it.

“Richie did very well too. You always see the glory work with Richie, with his big blonde hair, but the other work pleased me more, the dark arts of the game.

“And our centre combination Matt Scott and Alex Dunbar that will be the equal of any northern hemisphere team in a couple of years. It’s special.”

The Scots trailed 13-3 at ?half-time and it was no surprise as they were blitzed at the ?breakdown and second best at the scrum.

Italian stand-off Tommaso Allan – plain old Tommy when he knocked back a contract with Edinburgh last year – looked as if he would return to haunt the Scots with two penalties and a try, with Greig Laidlaw kicking three points for Johnson’s men.

Laidlaw had an afternoon to forget, ponderous in possession, although he kicked Scotland closer to the Italians early in the second half before Dunbar’s first score after Allan coughed the ball up.

It was the Scots’ first try in five Tests and when Chris Cusiter replaced Laidlaw after an hour they upped the tempo further as the Warriors star linked with Lamont to send Dunbar clear.

At 18-13 to the good the Scots’ joy was shortlived as Joshua Furno went over in the corner, with the conversion giving them a two-point lead that stood until Weir’s decisive kick.

Gray, dropped for the England defeat a fortnight ago, said: “I had no idea we were lining up for the drop goal. We were just burying our heads in the pack and trying not to touch the ball.

“It was the highest drop goal anyone has ever seen.

“This is a pick-up for the squad. We came in for a lot of criticism after England. We dug in and it wasn’t easy but this win shows the character of the squad.

“It has been a tough couple of weeks for me not being involved. I didn’t feel pressure from the outside but I did put pressure on myself.

“I wasn’t happy how I left it against South Africa in the autumn Tests and I wasn’t happy with what I did when I came off the bench against Ireland. I put pressure on myself to set a standard.”

Try star Dunbar added: “We know we did not play in the first half. We couldn’t put phases together and the penalties slowed us down.

“But in the second half we put a lot of things right and got quick ball, which was the main thing.

“I was taken off with cramp so I was on the bench when Dunky kicked his drop goal. The whole bench were calling for it.

“We’ve shown glimpses of what we can do. Now we must put in an 80-minute performance at home to France in two weeks.”